Very confused!

Katie
So I started bleeding 4-5 days before my period was to start. It was really heavy the first 2 days then practically non existent on the 3rd day. That night it picked back up just a little and then not much the 4th day. Took a  HpT 4th day and got faint line again. I have been getting them on and off it seems for almost a week. Or maybe some are Evaps, idk. 5th day hardly any blood just a tiny bit when I wiped. 6th day (today) brown spotting. What the heck is going on? Took an HPT last night again and got another faint line. We had sex on all the right days when ovulating. Have been extremely tired and itchy boobs for days. Have Researched: heavy implantation bleeding, dicidual bleeding, chemical pregnancy. No idea what's going on. My period is usually 4-5 days and always bleed the full length of days so it's weird for me to bleed only 2 days really. I have 1 child already. Period was supposed to start 24th-25th and started bleeding the 20th. Any ideas !??